0026377: Passing Handle objects as arguments to functions as non-const reference...

0026377: Passing Handle objects as arguments to functions as non-const reference to base type is dangerous

Operator of cast to non-const reference is declared deprecated to produce compiler warning if used (usually implicitly).

OCCT code is updated to avoid that cast, occurring when function accepting non-const reference to handle is called with handle to derived type.
For that, local variable of argument type is passed instead, and down-cast is used to get it to desired type after the call.
A few occurrences of use of uninitialized variable are corrected.